Color verification, verifying the condition of color reproduction of printed matters, is conducted by causing an image forming apparatus to print a chart in which color patches are arrayed and causing a color measurement device to read the chart. For example, an image forming apparatus outputs a chart without performing color management (color space conversion), a color measurement device measures colors of the chart, and a printer profile is created by using data of the measured colors. After the color management by using the created printer profile, the image forming apparatus outputs a chart, the color measurement device measures colors of the chart and color verification is performed by using the data of the measured colors. If a verification result indicates unacceptable color reproduction accuracy, color calibration is conducted on the color image forming apparatus by using its color calibration function, and the color image forming apparatus outputs a color chart again. Then, until a verification result indicating acceptable color reproduction accuracy is obtained, output of a color chart, color measurement, and color calibration are conducted repeatedly.